Is the Phantom so sensitive that you need a (1) hood for the camera lense to keep the sun away (2) guard to hold camera from breaking loose from the holder (3) ties on the gimbal (4) skids for better landing (5) bigger legs to better landing.  Everyone seems to need to sell improvements so you do not damage on landing or crash. Are these really needed?  and if so which one??? Tks

They are seen as modifications to allow you to use the product away from the test lab it was created and tested in....

Modifications or rectifications ,  only you know what you use yours for so........   

But yes,  bigger skids and legs for balance,  gimbal protective black box, as it is so fragile a gust of wind and an autumn leave flashing past it could traumatise it into never working again.....
If it does work it needs a sun cover to stop the blades interfering with the picture...

Despite being sold as "Your Flying Camera" , it will eventually just be "Your Flying camera platform" that may or may not involve a camera due to other reasons........

There are many other modifications that get a bit technical so I would research a bit more,  but overall.....

You can perform these modifications/rectifications on the vision, or on some cheap Chinese crap that wont survive your first 3 crashes....

Have fun checking out the competition...  I'm sure you will make the right decision just like we have...  

1. yes, a lens hood is required on all lenses, on all cameras...inc compacts, dslrs. the sun can burn a sensor in seconds if it enters through a lens.
2.yes...fairly obvious damage prevention measure imo
3.yes. these anti drop ties are needed o stop your gimbal separating. dont forget the isolators keep the gimbal in suspension.
4.yes..how else do you land if youre carrying a gimbal ??
5. yes, and again obvious that bigger legs provide more stability.

third party mods are not always improvements and can invalidate warranty. plus even if someone considers their mod an improvement, and it may well be, DJI may not consider it worthwhile cost wise to implement. at the end of the day its cost v profits that keep the business going.

lastly, i think you may be very excited when you see the new Insprie 1 which will be released very soon.